By now, you may have heard the peculiar explanation of how witches and wizards in J.K. Rowling’s universe relieved themselves before modern-day plumbing. As Entertainment Weekly reports, a section of the Pottermore website pertaining to the Chamber of Secrets entrance (which, if you recall, was in Moaning Myrtle’s bathroom) states that Hogwarts adopted plumbing in the 18th century. Before that, spells were cast to eliminate excrement—or perhaps blast it into another dimension.

“Hogwarts’ plumbing became more elaborate in the eighteenth century (this was a rare instance of wizards copying Muggles, because hitherto they simply relieved themselves wherever they stood, and vanished the evidence),” the site states in an essay by Rowling. This was initially revealed in 2015, but Pottermore's recent tweet on the subject has been causing a stink.

A lot of people aren’t satisfied with this unsavory explanation—"witches and wizards, some highly sophisticated beings who created complex magical governments and tamed the fiercest beasts, at one point just pooped themselves,” Entertainment laments—but it’s worth noting that the claim does pass a historical fact check of sorts.

According to Rowling, Hogwarts was founded in the year 990 C.E.—more than 600 years before Sir John Harington, the godson of Queen Elizabeth I and a distant relative of Game of Thrones star Kit Harington, invented the first flush toilet. Even though this technology existed in the 16th century, Harington only made two toilets: One for himself and one for his royal godmother. The first patented flush toilet didn’t arrive until 1775, thanks to a different design by watchmaker (and toilet inventor) Alexander Cummings. So the timing checks out.

Of course, people didn’t just pee themselves or pop a squat on the ground prior to working toilets, which is why so many people are baffled by Rowling’s explanation. Chamber pots and outhouses were used throughout much of human history, and members of the British ruling class had more luxurious arrangements. In the 16th century, King Henry VIII did his business atop a padded chair—covered in sheepskin, black velvet, and ribbons—with a chamber pot beneath it. However, male courtiers did sometimes do their business wherever they felt like it (palace stairwells were one popular location in France).

As for Hogwarts’ plumbing situation, it may sound like a gross and unnecessary detail, but it’s actually relevant to the story. According to a Pottermore essay penned by Rowling, the entrance to the Chamber of Secrets was nearly revealed when the school decided to build a bathroom on the site. However, a student and direct descendent of Slytherin named Corvinus Gaunt played a part in concealing its entrance—“even after newfangled plumbing had been placed on top of it.”

[h/t Entertainment Weekly]